In the manufacture, retreading, and use of tires, the temporary placement of one or more sensors along the inside surface of the tire for inspection is useful. Through such inspection, the sensors can be used to obtain important measurements, testing, and other information for both new and used tires. Such information can sometimes be used to determine e.g., whether certain defects and/or damage are present that might not otherwise be visible to the naked eye or obtainable from outside the tire.
By way of example, a known tire construction uses reinforcement cords or support elements that extend from bead to bead through the sidewalls, shoulders, and tread section of the tire. Sometimes referred to collectively as the tire carcass, these cords are typically anchored in the beads and maintain the overall shape of a pneumatic tire as the tire is inflated and used. Such cords are usually oriented substantially along the radial direction (a direction perpendicular to the axis of rotation) through the sidewalls and can include e.g., a ferrous metal.
During use of the tire, these cords may be damaged e.g., from impact with objects in the roadway, travel over curbs, and other damaging events. In some situations, the cords may be completely broken during such an event. Unfortunately, this damage may not be readily discoverable from a visual inspection of the exterior of the tire because the cords are contained within the rubber materials used to construct the tire.
Commercial tires are commonly reused after a process referred to as retreading. With retreading, worn tread is removed from the tire and a new tread belt or tread section is installed onto the tire. Replacement of the tread is less expensive than replacing the whole tire and allows additional mileage to be obtained using the same tire carcass.
Before replacing the tread, however, it is advantageous to inspect the tire, including the cords of the carcass, for damage or wear. In certain situations, inspection may reveal that replacement or other repair of the tire is required rather than retreading. However, as stated above, not all damage to interior elements such as e.g., the cords of the carcass are readily apparent from a visual inspection alone. As the cords for commercial tires such as heavy truck tires are frequently constructed from a ferrous material, one or more sensors can be used to detect cord breaks not otherwise ascertainable from a visual inspection of the tire.
It is desirable to automate inspection processes such as the one described above so that multiple tires may be inspected economically and expediently. Certain challenges are presented for such automation. For example, tires come in a variety of shapes and sizes. The profile and width (along the axial direction) can vary substantially from tire to tire. Some sensors require placement at the inside surface of the tire either in contact with the inside surface or in close proximity thereto. In addition, during certain tire inspections, the tire may need to be rotated during the inspection process so that the sensor(s) can scan the entire sidewall. However, tires may have one or more features along the inside surface of the sidewall such as onboard sensors, patches, and other devices that may project above the inside surface. These features can damage or otherwise interfere with a sensor attempting to scan the inside surface.
Accordingly, a device that can properly position one or more sensors along the inside surface of the tire would be useful. Such a device that can be repeatedly deployed along the inside surface of tires of varying shapes and sizes would also be beneficial. Such a device that can also accommodate features projecting from the inside surface of the tire would be helpful. The ability to deploy one or more of such devices simultaneously along both sidewalls of the tire would be particularly useful.